[docs] Advise users not to specify the version explicitly
Merge pull request #1670 from igorw/patch-7

[docs] Advise users not to specify the version explicitly
Fix tests
Fixed potential undefined index in ArrayLoader.php

A source without a reference is invalid.
Merge pull request #1671 from thomas-gay/master

Fixed potential undefined index in ArrayLoader.php
Fixed CS
Merge pull request #1672 from deguif/master

Fixed CS